Maserati Biturbo

Cheap to get into but expensive to run, Modena's two-turbo terror can be a rewarding drive

Feature Article from Hemmings Sports & Exotic Car

Carmakers seem never to be satisfied occupying their spot in life. Everyone wants to be someone else. Look at Jaguar's downmarket X-Type experiment. Pontiac keeps thinking they want to be like BMW. Porsche is making an SUV. Volkswagen, with the Phaeton, went squatting on Mercedes S-Class turf. Mercedes, meanwhile, was aiming for the Golf market with the A-Class. None of them, save arguably for Porsche, has made a great deal of headway.
Maserati seemed to have that same sort of crisis about a quarter-century ago, when the first Biturbos arrived. The truth of the matter was a little darker than this: Maserati, maker of genre-defining GT cars, was slurped up by Citroën back in the '60s and spat back out in 1975 when the French maker was looking to save its own hide and shacked up with former rival Peugeot. Alejandro deTomaso, who had worked to turn around both Moto Guzzi and Benelli motorcycles, and had been overseeing Innocenti, was appointed by the Italian government to sort it all out.
The answer, deTomaso reasoned, was volume: something powerful enough to deserve the Maserati name, yet reasonably priced enough that they could achieve volume production. Granted, reasonable pricing and volume were both relative terms: The Innocenti plant in Milan, where many Biturbos were built, had a capacity of about 10,000 cars per year--and had an advanced rust-guard dipping facility on-site that the Modena works didn't possess.
The car that sprang from that brief was the Biturbo. Originally, it was a sharply styled coupe, bringing then-contemporary Quattroporte styling and squat, bulldog proportions to a BMW 3-series-size package. The Biturbo name came from the same school of clever marketing that called Maserati's big four-door the Quattroporte (Italian for "four-door")--the Biturbo's engine did, indeed, sport a pair of oil-cooled IHI RHB-51 turbos, one on each bank of the all-aluminum 2.5L SOHC V-6. Two turbos were chosen, the story goes, because smaller turbos would be able to spool up more quickly, thus eliminating the dreaded turbo lag that so many boosted cars suffered from in those days. Max boost was at 11 pounds, with a computer-controlled wastegate bleeding away the excess. The Biturbo employed three-valve heads (two intake, one exhaust), which were said to aid charge turbulence and give the spark plug a better location to ignite it all. Sounds high-tech, right? Particularly for the early '80s. So it was a bit of a shock to learn that under that cast plenum lay a two-barrel Weber carburetor. Even so, the resulting 185hp at 5,500 rpm and 208-lbs.ft. of torque at 3,000 rpm were considered strong figures for their day--enough, in fact, to keep the Biturbo on pace with a Ferrari 308 Quattrovalvole.
Initially, a ZF five-speed was the only transmission; later, a three-speed automatic was also available. A fully independent suspension featured MacPherson struts, coil springs and an anti-roll bar in front, while the rear featured coils and semi-trailing arms. The lack of a rear anti-roll bar allowed for spirited cornering, allowing as much as .78g on its 195/60HR14 Pirellis.
Maseratis traditionally had sumptuous interiors, to fit their GT brief; the Biturbo could be no exception. Early cars had a largely suede (really Alcantara)-covered interior with genuine leather seating surfaces and a strip of wood veneer across the dash and doors, and wool carpets, which can be prone to sun damage. The traditional clock appeared front and center on the instrument panel. Later seats, starting around 1987, were all leather and held up far better; the faux-wood strip was removed and replaced with genuine Carpathian elm. Rack-and-pinion steering was fully manual at first; power assist came halfway through the Biturbo's life in America.
Considering that a Khamsin was a $40,000 car in the late '70s, a Maserati costing $25,000 in 1984 seemed a relative bargain, doubly so when it offered serious sports-car performance for roughly Mercedes 190E 2.3 money. In the U.S., sales started off fairly strong: 2,023 in 1984, 1,190 in 1985, and 1,298 in 1986. This means that the early cars are the most plentiful, but thanks to continual evolution, and a mind-boggling array of drivetrain changes, the later cars are widely regarded as superior machines. A Spyder variant came in starting in 1986, and a four-door sedan called 425 (four-door, 2.5L engine) joined mid-season.
By most accounts, model year 1987 is the first reasonably reliable year for the Biturbo: Fuel injection became standard, the IHI turbos were now air-to-water intercooled and liquid-cooled, the fusebox issue was sorted, wheels switched to a five-lug pattern, and interiors were significantly upgraded. A bump to 2.8L in displacement, and a 225hp power rating, spiced things up nicely. The Biturbo name disappeared, though fans of this generation of car still use the name to describe it. The Spyder remained, the coupe was the 228 and the four-door, for reasons unknown, was called the 430 (despite still having a 2.8L engine).
Still, sales continued to fall. Name change or not, their reputations had started to precede them: Maseratis were fun, expensive-to-maintain little grenades. No Biturbos were imported in 1988 at all--dealers were busy selling off their backed-up inventory. By 1990, American sales had dipped to just 240 units, and Maserati retreated back across the Atlantic. Variants of the Biturbo platform continued on in Europe well into the 1990s, with names like Ghibli, Shamal and Karif; mechanical upgrades continued, many of which can be retrofitted to previous American-spec Biturbos.
Once all was said and done in the mid-'90s, more than 38,000 Biturbos were built for worldwide consumption in the platform's dozen years of life. More than 5,000 made it to the States.
The Biturbo range quickly developed a reputation of being cheap to get into but would bleed your AmEx Black card dry with repair costs if you let it. But the later cars, from the fuel-injected era, tend to be far less finicky than the carbureted cars. Our sample car, an '89 Spyder five-speed, is owned by Doug Magnon of Riverside, California; he owns one example of every Maserati street car ever built, from the late '40s AC to a new MC12, so his collection wouldn't be complete without one on hand. Doug pointed us toward Bill Duval of Santa Barbara, California, who at this writing owns a total of eight Biturbos of various years and states of tune (including parts cars), so he can speak to these from practical experience. "The '84 and '85s can be real bargains ... if you get one that someone's worked on already, you won't be out a lot of money for parts. I can't imagine someone doing a total restoration on one ... but that's the owner you want to find to buy his car." Think they're not out there? "I bought an '87 Spyder a while back for $11,000, and the owner gave me $39,000 in receipts (including the cost of the car new). That's who you want to buy a car from." Be careful, though: "Some of the early cars had belt-tensioner issues," Duval warns. "Make sure that belt is where it's supposed to be, or you may as well throw the engine away." The differentials in earlier cars were a weak point. Also, it's well-known that removing the catalytic converter will gain you 25 horsepower: if you live in a state that tests for emissions, like California, make sure it's there.
The Biturbo lives in a strange netherworld: Maserati clubs tend to shun Biturbos and their owners, according to Duval; at the same time, no Biturbo-specific clubs have spring up in the States to allow owners to commiserate. (There are a couple of European Web pages devoted to the full run of these machines, however.) Luckily, parts are available, if expensive: MIE, an offshoot of the Maserati Owner's Club based in Seattle, has just about everything you'd want to repair one. At the same time, early parts cars are often available for $500. "They're handy to have around," admits Duval. "You may need to change a lot of things out, and it's just easier to buy a parts car. Here's an example. I needed a new touchpad heater control. One place wants $536 and a core; another wants $395 for a working unit. That's a lot of money for a part." Particularly when a whole working car is valued at $7,000, and you can get a parts car for the cost of a new piece.
A decent-running Biturbo may require more care and feeding than other performance machines of the era, but it may also be the easiest way into that rare society: that of the Maserati owner. Besides, says Duval, "It's better than owning a Chrysler TC."
Specifications
Engine: SOHC, V-6, Aluminum block, twin IHI RHB-51 turbos
Horsepower: 2.5L: 185 @ 5,500 rpm; 2.8L: 225 @ 5,600 rpm
Torque: 2.5L: 208-lbs.ft. @ 3,200 rpm; 2.8L: 246-lbs.ft. @ 3,500 rpm
Gearbox: ZF five-speed manual; three-speed automatic (to 1988); four-speed automatic (1989-on)
PERFORMANCE
2.8L: 0-100 kph (0-62 mph): 5.9 seconds. Top Speed: 146 mph.
Standing KM: 26.1 seconds
Source: Maserati Test Specifications
DIMENSIONS
Length: 159.2 inches
Width: 67.5 inches
Height: 51.6 inches
Curb Weight: 2,394 lbs. (1984-'88); 2,780 (1989-'90)
Production
1984: 2,023
1985: 1,190
1986: 1,298
1987: 300 (Spyder only)
1988: 0
1989: Sales data unknown
1990: 240 (Spyder only)
(U.S. sales figures)
ENGINE
In general, most of the bugs were worked out in later years--a reason to find an '89 or '90, if possible. The cast plenum over the carburetor (on early cars) is prone to cracking if it's torqued down too tightly, and the cover can contribute to cooking seals.
Two small screens, covering a couple of small oiling holes used to lubricate the top end of the engine, are easily clogged. The finned, cast-aluminum oil pan on all Biturbo variants is very low to the ground and is prone to crushing. The cam box covers also tend to leak. Be careful about cooling down the turbos, particularly in the oil-cooled '84s and '85s. An upgrade to the '86-up water-cooled IHI turbos can help. So will a switch to fully synthetic oil.
Duval claims that the engines themselves are strong, though they're a pain to work on--"It's tough to do a valve job; you need to use shims, the starter is in the V of the engine near the firewall, and you can't get to it without removing the intake manifold," he says. Judicious maintenance will pay dividends. "The cams are run off a belt," says Duval. "I change 'em every 6,000 miles.
STEERING, SUSPENSION AND BRAKES
"None of them have rear anti-roll bars unless they're aftermarket," reports Duval. "The spare tire is slung under the trunk, so there's not much room for a bar." Handling can be "twitchy ... you have to be brave to drive 'em fast, and use a lot of throttle steer. Once you're committed to a corner, you don't lift." The brakes themselves are strong, but "under heavy braking, you have to hang onto the wheel or you'll swap ends." The handbrake is considered merely adequate, and then only when in top shape.
The rear subframe is also prone to cracking on the early cars, according to our expert--a problem that seems to have gone away with later models. It's recommended that wheel bearings be repacked once a year or so, as they are generally considered to be a weak point. Luckily, non-Maserati bearings are available.
The steering rack can be an issue; beyond the usual cracked boots and leaking oil, fluids leaking onto the steering column collapse could spell trouble.
BODY
"Be careful with that high-carbon steel the Italians use," warns Duval. "I had an '87 Spyder I changed the windshield on, the guy scratched the drainage channel, and I later had to have it taken apart and rewelded. Check wherever the drainage goes, and make sure the holes aren't clogged with dirt: around the windshield, around the rear windows of the coupes, where the seals are, and look along the bottom edge of the doors--they've got Mickey Mouse drains inside the doors." Beyond rust issues, the windscreen tends to delaminate (the only cure: buy a new one), and the door stoppers require lubrication (they work properly when not squeaking) or else they will break. Spyders should also have their roofs inspected: If part of the roof structure seems too tight or is attempting to burst through the top material, the car has likely been broken into. Rear windows, a common entry point for crooks, are often fixed partly by stretching some of the top fabric over a new window.
ELECTRICAL
Nearly all sources we checked with admitted that the fuse box is an issue. "It's a sandwich of three layers that's been folded over and then plug-soldered, so they have an overloaded powerpoint," Duval explained. The problem appears to be exacerbated by the air conditioning--the design was insufficient to take the strain of the compressor, and the fix coaxed electrical gremlins from elsewhere in the car to come out into the light of day. The good news is that a replacement fuse-box kit is available. (Duval recommends MIE in Seattle, run by the Maserati International club; "They bought Maserati's remaining inventory on these cars when the company left the country in 1990.") The stock alternator is a 14-volt, 65-amp unit that some feel isn't up to the task. There are various tales of stock GM and Bosch alternators with metric threading slotting into place with little fiddling. "You can substitute a GM part for a Maserati one, but you'd better know what you're doing," warns Duval.
DRIVETRAIN
The transmissions used in the various Biturbos, a ZF five-speed gearbox or a three- or four-speed automatic, are generally considered strong, though the stick cars may require some warming up before the synchros work smoothly. Early cars were also known to have weak clutches; a later factory replacement clutch will take care of any issues.
"These engines made enormous amounts of torque," says owner-expert Duval, "and the factory ring and pinion just wasn't strong enough." Some claim that a combination of heat and a high sustained speed did in the early diffs. Even so, the fix is known as the Ranger, which debuted in the '88 model year cars, easily identified by a tag stamped "Q9" under one of the bolts. This still was an open rear--a Torsen differential wasn't introduced till the mid-'90s. Also, removing the catalytic converter is said to be good for an honest 25 horsepower across the board, regardless of engine displacement, carburetion or tune.
PRICE GUIDE

Low

Average

High

1984 Coupe

$3,000

$5,000

$7,000

1987 425

$3,000

$5,000

$7,000

1990 Spyder

$7,000

$12,000

$16,000

(Deduct 25 percent from all prices for automatic transmission)
PARTS PRICES
Brake caliper kit $55 (rear), $80 (front)
Brake master cylinder $495 (exchange)
Carb rebuild kit $90
Choke cable $150
Clutch slave cylinder $150
Disc brakes $200
Distributor rotor $190
Driveshaft center support $275
Exhaust system $1,100
Fender $430
Fuel pump $330
Fuel sender w/gasket $95
Head gasket set $380
License plate lamp $50
Oil filler cap $90
Oil pump rebuild kit $190
Shock absorber $350 (front); $240 (rear)
Suspension control arm $75
Suspension lower ball joint $75
Suspension stabilizer drop link $70
Throttle cable assembly $200
Tie rod end $45
Water pump $300
RECENT ADS
1984 Biturbo, gray/tan, five-speed, excellent condition overall, just serviced, $4,750.
1986 Spyder, red/tan, automatic, 33,000 miles, fresh service and top end, $8,500.
1987 425 sedan, 97,000 km, never winter driven, A/C, power windows, sunroof, tan leather interior. $7,500 obo.
1989 228, one of 70 produced, 50,000 miles, five-speed, no expense spared on maintenance, former Concorso Italiano winner, gray with cream leather, recent service, always garaged, $23,499.
SPECIALISTSMIE
1620 Industry Dr. S.W., Suite F
Auburn, Washington 98001
Ph: 253-833-2598
Fax: 253-735-0946
E-mail: mie@maseratinet.com
CLUB CORNERwww.themaseraticlub.com/tmc.html
Check here for a regional Maserati club in your area.
Maserati Club International
1620 Industry Dr. S.W., Suite F
Auburn, Washington 98001
Ph: 253-833-2598
Fax: 253-735-0946
E-mail: mci@maseratinet.com USA
Viewpoint
I bought this Spyder in 2004 with the idea that it would be a fun driver at club events, and that it would represent the Biturbo in my Maserati collection. Due to reliability concerns, I only wanted a very late Biturbo Spyder, and for performance, only a manual transmission. This car fit the bill. It's a very clean, original and low-mileage (25,000) example. Nearly all Biturbo Spyders that came to the U.S. were automatics; the main exception are the '89s, which all came with five-speed manuals. The '89-'90 year models were the most developed, well-appointed and reliable of the Biturbo series that were imported to the U.S. Other than an MIE lowering kit, which dropped it about an inch, and the stereo, it's factory-stock. I drive it about 500 miles a year without any problems.
-Doug Magnon

This article originally appeared in the October, 2007 issue of Hemmings Sports & Exotic Car.